So I finally bit the bullet and picked up a Sigma fp for a documentary project I'm shooting around Seattle next month and now I'm stuck in the adapter rabbit hole. I've got a bunch of Canon EF glass—mostly the 24-70mm and a 50mm prime—that I really want to use without buying all new L-mount lenses because honestly I'm broke after buying the camera body lol.

I did some digging and obviously the Sigma MC-21 seems like the official choice but I've read some weird stuff online about it not supporting continuous autofocus or being super slow with older Canon lenses which is a huge deal for me since I'm mostly shooting handheld and following people around. Then I saw the Metabones Smart Adapter but that thing is like double the price and I cant really tell if the performance boost is actually worth the extra cash or if its just hype.

Here is what I am looking for:

• Budget: Trying to stay under $250 or $300 if possible
• Use case: Documentary work, lots of movement, mostly video
• Must have: Decent autofocus speed and solid build quality (no wiggling)
• Timeline: Need to have this figured out by the end of the month

Is the MC-21 actually as bad for video AF as people say or am I overthinking it? Or is there some other brand I am totally missing like Commlite or something...